Recent work by others and preliminary data from this department have suggested that farmers are at greater risk for certain types of cancer than had been generally recognized. Using the Iowa agricultural population as a base, further exploration will include: an improvement in rate and quality of occupational recording. This will be done by linkage with drivers' license tapes, direct mail questionnaires, recently completed independent studies and completion of death certificate coding. Both proportionate and standardized incidence and mortality rates will hen be caluculated for all cancers by main occupational groups.